Collapsible serving cart



April 1, 1969 u. WERNER COLLAPSIBLE SERVING CART I of 4 Sheet Filed Nov.22, 1967 A ril 1, 1969 u. WERNER 3,436,092

CQLLAPSIBLE SERVING CART Filed Nov. 22, 196? Sheet 2 of 4 Inventor:

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his Ahomey April 1, 1959 u. WERNER 3,436,092

COLLAPSIBLE SERVING CART Filed Nov. 22, 1967 Sheet 3 of 4 Udo WERNER5,.- M (71.

his AHorney Inventor.-

April 1, 1969 u. WERNER COLLAPSIBLE SERVING CART Sheet Filed Nov. 22,1967 3,436,092 COLLAPSIBLE SERVING CART Udo Werner, Solingen-Ohligs,Germany, assignor t Bremshey 81 Co., Solingen-Ohligs, Germany, a firmFiled Nov. 22, 1967, Ser. No. 685,089 Claims priority, applicationGermany, Dec. 31, 1966, B 90,555 Int. Cl. B62d 21/14; B621) 1/04, 3/02US. Cl. 280-36 Claims ABSTRACT OF THE DISCLOSURE A collapsible servingcart wherein table top members are capable of being swung betweencollapsed, rest positions where they are in vertical planes andhorizontal, operative positions where they are in horizontal planes. Thetable top members are carried by a frame means, and four rollerassemblies are provided to support the serving cart for rollingmovement. Four arms are respectively operatively connected with theroller assemblies and extend laterally therefrom to the frame means, anda connecting means connects a pair of these arms with one of the tabletop members to swing the arms outwardly away from the frame means inresponse to swinging of this one table top member from its verticalinoperative position to its horizontal operative position and forswinging the arms back in toward the frame means in response to returnof the table top member from its horizontal operative position to itsvertical rest position.

Background 09 the invention This invention relates to serving carts.More particularly this invention relates to serving carts which arecapable of being collapsed into a relatively small space when not usedand which are capable of being expanded into an operative position whenthey are used.

The invention relates in particular to a type of serving cart whereinthere are at opposed lower ends of the cart swingable, laterallyextending arms which are operatively connected at their outer ends toroller assemblies which support the cart for rolling movement. Thesearms are respectively swingable about vertical axes to displace therollers outwardly away from the frame means of the serving cart when thelatter is to be used and to swing the rollers inwardly to the framemeans when the serving cart is collapsed in its position of non-use. Theserving cart also has swingable table top members which are capable ofbeing swung from vertical rest positions into horizontal operativepositions, and a structure is provided for automatically turning thearms which are connected to the roller assemblies outwardly away fromthe frame when the table top members are swung from their vertical restpositions to their horizontal operative positions.

Serving carts of this general type have many different uses. They permitthemselves to be situated in a relatively small space when they arecollapsed in their position of non-use, while when they are used, one ormore of the table top members can be swung to a position of use toprovide a relatively large surface area available for supporting anydesired articles. While a pair of the table top members can be situatedin a common plane in their horizontal positions of use, it is possibleto turn only one of these table top members from its position of non-useinto its position of use, if desired, and in such a case the remainingtable top member, which continues to extend vertically, can be used forother purposes such as for supporting a book, for example.

Known serving carts of this general type require a certain skill andexperience on the part of the operator in order to displace the cartbetween its collapsed and ite States Pate O ice expanded positions, andin addition the operator is required to exert a considerable forceduring manipulation of the part to displace it between its collapsed andextended positions. These latter considerations are particularlyapplicable in connection with swinging of the table top members fromtheir vertical rest positions to their horizontal operative positions,because during these latter operations it is necessary with the knownconstructions to overcome spring forces which act to hold the arms whichare connected to the roller assemblies in their inwardly swung positionsin the immediate vicinity of the frame of the cart. In addition, errorsin the operation of the known structures easily occur. During return ofthe table top members to their vertical rest positions, for example, thesprings which act on the arms which are connected to the rollerassemblies snap these arms with considerable impact back into their restpositions. This operation results in undesirable stressing of thecomponents of the cart and in creation of undesirable noise, and duringimproper manipulations it can happen that objects or even limbs of theoperator may be clamped between components of the table, resultingperhaps not in a dangerous situation but certainly in an undesirableinconvenience and a troublesome situation.

Summary of the invention It is accordingly a primary object of thepresent invention to provide a serving cart of the above general typewhich will avoid the above drawbacks.

In particular, it is an object of the present invention to provide aserving cart which will retain all of the advantages of known servingcarts while at the same time avoiding the drawbacks thereof.

In particular, it is an object of the present invention to provide aserving cart wherein swinging of a table top between rest and operativepositions will result in auto matic swinging of roller assembliesoutwardly to their operative positions, so that the positions of theroller assemblies are determined by the positions of the table topmembers in a fully automatic manner.

In addition, it is an object of the present invention to provide aconstruction of this type wherein it is unnecessary for the operator toovercome any spring forces, except perhaps the spring force of a detentstructure which releasably maintains the table top members, for example,in their inoperative positions and which hardly requires any appreciableexpenditure of energy in order to be overcome.

Furthermore, it is an object of the invention to provide a constructionwhich requires only application of pressure to a table top member inorder to place the latter and roller assemblies operatively connectedtherewith in their operative positions. The same is true for the reverseoperation where it is only necessary in accordance with the invention toswing a table top member back to its inoperative position in order toautomatically return the roller assemblies inwardly toward the frame ofthe cart to their inoperative positions.

A transmission which will provide for automatic swinging of the rollerassemblies outwardly away from the frame during swinging of the tabletop member and back to the frame during return of the table top memberto its inoperative position requires, according to the knownconstructions, a complex assembly of elements since the table top memberswings about a horizontal axis while the arms which are connected to theroller assemblies respectively swing about vertical axes.

It is accordingly yet another object of the invention to provide aconstruction wherein this connecting means which interconnects the armswith the table top members is of an exceedingly simple and reliableconstruction solving the problem of the transmitting movement from thetable top members to the roller arms in a very simple and highlyreliable manner.

In particular, it is an object of the invention to provide for aconnecting means of this latter type only a single shifta-ble component,in the form of a sleeve, while the remainder of the structure isdirectly connected with the arm which is connected to the rollerassembly.

In accordance with the invention a frame means of the serving cartsupports a pair of table top members for swinging movement betweenvertical rest positions and horizontal operative positions where thetable top members are situated in a common plane. Four roller assem-'blies are provided to support the cart for rolling movement, and fourarms are operatively connected to the roller assemblies and extendlaterally therefrom to the frame means. A connecting means connects apair of these arms to one of the table top members for swinging this onepair of arms outwardly away from the frame means in response to swingingof this one table top member from its vertical inoperative or restposition to its horizontal operative position, as well as for swingingthe arms back to the frame means in response to return of this lattertable top member from its horizontal operative position to its verticalrest position. In particular, this latter connecting means includes apair of vertically extending rotary spindles respectively fixed at theirbottom ends to ends of the arms which are adjacent to frame means, andat the elevation of the table top member these spindles respectivelycarry sleeves which are prevented from swinging about the axis of thespindles while being vertically displaceable with respect thereto, thesesleeves respectively having pin-and-slot connections with the table topmember, so in response to swinging of the latter the sleeves will bevertically displaced along the spindles. The sleeves and spindlesrespectively have threaded connections to provide for rotary movement ofthe spindles about their axis in response to vertical displacement ofthe sleeves, and as a result of this vertical displacement of thesleeves the turning spindles will turn the arms which are fixed theretoso as to swing the roller assemblies outwardly away from or back towardthe frame means.

It is preferred to provide a construction where the sleeves respectivelyhave the laterally extending projections formed with slots which receivepins which are respectively fixed to the table top member, so that inresponse to swinging thereof the sleeves will be vertically displaced.

Brief description of drawings The invention is illustrated by way ofexample in the accompanying drawings which form part of this applicationand in which:

FIG. 1 is a perspective illustration of one possible embodiment of aserving cart according to the invention, shown in its collapsedposition;

FIG. 2 shows the structure of FIG. 1 with one pair of vertically alignedtable top members already in their operative positions while the secondpair of table top members, which are in vertical alignment with eachother, are shown in an intermediate position between their rest andoperative positions;

FIG. 3 shows the parts with one pair of vertically aligned table topmembers in their operative positions and the other pair in theirinoperative positions and with an outer covering plate of a hollow endwall assembly removed so as to show the structure therein;

FIG. 4 shows, at an enlarged scale as compared to FIG. 3, the structureat the upper part of the latter with one upper table top member shown inits horizontal op erative position and with the other shown duringmovement between its operative and non-operative positions;

FIG. 5 shows the upper part of the serving cart in the position of FIG.3 in a vertical end view with the parts being shown in FIG. 5 at a scalelarger than that of FIG. 3;

FIG. 6 is a fragmentary sectional plan view taken along the line VI-VIof FIG. 3 in the direction of the arrows;

FIG. 7 is fragmentray sectional elevation taken along the line ofVII-VIII of FIG. 3 in the direction of the arrows;

FIG. 8 is a fragmentary sectional plan view similar to that of FIG. 6but showing a different embodiment of the structure of the invention;

FIG. 9 shows one of the connecting assemblies of FIG. 8 in elevation;

FIG. 10 is a fragmentary sectional elevation similar to FIG. 7 butshowing the structure of FIG. 8.

Description of preferred embodiments The example of the invention whichis illustrated in FIG. 1 includes a frame means composed of verticallyextending hollow end wall members 1 which are rigidly connected witheach other by way of horizontal tubes 2 which extend between and arefixed to the hollow end wall assemblies 1. In this way a rigid,rectangular frame means is provided for the serving cart. The hollow endwall members 1 of the frame means form at the same time housings for theconnecting means which interconnects and transmits movement between theswingable table top members and roller assemblies, as explained below.This connecting means which transmits the movement between the swingabletable top members and the roller assemblies is shown in detail in FIGS.2-5 wherein an outer cover plate of one of the hollow end wallassemblies 1 is removed to illustrate the structure therein.

In the illustrated example the pair of hollow end wall assemblies 1 ofthe frame means provide a supporting structure for a total of fourswingable table top members 3, 3 and 4, 4. Thus, an upper pair of tabletop members 3 are respectively in vertical alignment with a lower pairof table top members 4. The upper pair of table top members 3 have acommon horizontal turning axis about which they swing, and the pair oflower table top members 4 also have a common horizontal swinging axissituated beneath the common swing axis of the table top members 3. Forthis purpose each end of each table top member 3 carries a suitableplate formed with an opening through which a pivot pin 5 extends, thispin 5 being carried by an inner wall of each hollow end wall assembly 1,and the plates which are fixed to the adjoining ends of the pair oftable top members 3 have overlapping portions placing their openings inalignment and through which the pin 5 extends into an opening in theinner wall of the adjoining hollow end wall assembly 1. In this way thepair of table top members 3 are swingable about the common axis of apair of pivots 5 carried by the end portions 1 of the frame means, andin much the same way the lower pair of table top members 4 are swingableabout the common axis of the pair of pivot pins -6 which are carried bythe inner walls of the end wall portions 1 of the frame means at thelower regions thereof. The pins 5 and 6 at one end of the table topmembers are visible in FIG. 2.

The connecting means which interconnect the table top members with theroller arms referred to below include in each hollow end Wall assembly 1a pair of vertically extending rotary spindles 7 supported in the hollowend wall assembly 1 for rotary movement about their vertical axes,respectively. The lower ends of the spindle 7 have portions of reduceddiameter, for example, extending through openings in a lower wall ofeach hollow end wall assembly 1, and these lower reduced portions of thespindles 7 are fixed to the inner ends of a pair of laterally extendingarms 8 which are respectively connected operatively to a pair of rollerassemblies 9. This structure is of course repeated at the other hollowend wall assembly 1. The arms 8 are relatively short and in the form oflevers operatively connected at their outer free ends, where they arecranked downwardly, to the conventional roller assemblies 9,respectively. When the serving cart is in its position of non-use,illustrated in FIG. 1, the crank arms 8 are all swung inwardly closelyadjacent to the frame means 1, 2.

The connecting means include, in addition to rotary spindles 7, aplurality of sleeves which are situated approximately at the elevationof the upper table top members 3 and through which the spindles 7respectively extend, these sleeves 10 being axially shiftable along thespindles 7, respectively. These sleeves 10 respectively have threadedconnections with the spindles 7. In the embodiment of FIGS. 1-7 thethreaded connection between the sleeves and the spindles is provided byway of cross-pins 11 which are respectively fixed to and extend acrossthe sleeves 10, the spindles 7 being of a hollow tubular constructionand being formed with opposed helical slots 12 through which the pins 11extend, so that in this way a threaded, screw-type of connection isprovided between the sleeves and spindles, respectively. Thus, eachtubular spindle 7 has opposed wall portions provided with a pair ofhelical slots 12 wound in the same direction about the axis of thespindle 7 and through which a cross-pin extends, this cross-pin beingfixed to the sleeve 10 which surrounds the particular spindle 7.

In addition, the connecting means for interconnecting the arms 8 withthe table top members 3 includes laterally extending projections 13integral with and projecting laterally from the sleeves 10, theseprojections 13 being formed with horizontally extending slots 14 whichrespectively receive pins which are fixed to ends of the table topmembers 3. This construction is illustrated in FIGS. 5-7. In FIG. 5 thelaterally extending projection 13 of the right sleeve 10 is broken awayso as to render the pin 15 clearly visible. Thus, each table top member3 has a pair of these pins 15 respectively fixe'd to and projecting fromits opposed ends, and these pins 15 which are fixed to each table topmember 3 have a common axis and opposed helical slots 12 through whichthe pins 11 extend, so that in this way a threaded, screw type ofconnection is provided between the sleeves and spindles, respectively.Thus, each tubular spindle 7 has opposed wall portions provided with apair of helical slots 12 wound in the same direction about the axis ofthe spindle 7 and through which a cross-pin extends, this cross-pinbeing fixed to the sleeve 10 which surrounds the particular spindle 7.

In addition, the connecting means for interconnecting the arms 8 withthe table top members 3 includes laterally extending projections 13integral with and projecting laterally from the sleeves 10, theseprojections 13 being formed with horizontally extending slots 14 whichrespectively receive pins 15 which are fixed to ends of the table topmembers 3. This construction is illustrated in FIGS. 57. In FIG. 5 thelaterally extending projection 13 of the right sleeve 10 is broken awayso as to render the pin 15 clearly visible. Thus, each table top member3 has a pair of these pins 15 respectively fixed to and projecting fromits opposed ends, and these pins 15 which are fixed to each table topmember 3 have a common axis and this latter axis is spaced from theswing axis of the table top member so that the common axis of the pins15 of each table top member is situated at a predetermined distance fromthe swing axis defined by the common pair of pivots 5. The inner wallsof the hollow end portions 1 of each frame means are formed with arcuateslots 16 extending along part of the circle whose center is in thecommon axis of the pivots 5, and the pins 15 extend through these slots16 and are movable therealong during swinging of the table top members3. The thickness of the lateral projections 13 of the sleeves 10 issmall enough to enable these sleeves to be accommodated in the spacebetween the inner and outer walls of each hollow end wall assembly 1,while at the same time these inner and outer walls coact with thelateral projection 13 to prevent turning of the latter and the sleeve 10about the' axis of the spindle 7.

Thus, by way of the pair of pins 15 fixed to the opposite ends of eachtable top member 3, the latter is operatively connected through apin-and-slot connection with a pair of opposed sleeves 10. Swinging of atable top member 3 will therefore result in axial displacement of a pairof opposed sleeves 10 on a pair of opposed spindles 7 which are carriedby the pair of hollow end wall assemblies 1. This axial shifting of thepair of sleeves 10 which are operatively connected in this way with atable top member 3 will result in turning of the spindles 7 whichrespectively extend through the sleeves, because of the threadedconnection provided by way of cross-pins 11 and the helical slots 12,and thus when a table top member 3 is swung downwardly from its uppervertical position to its lower, operative, horizontal position, thespindles 7 operatively connected thereto necessarily swing in directionswhich will swing the pair of crankarms 8 connected thereto outwardlyaway from the frame means, to displace the roller assemblies 9 connectedto the latter pair of arms 8 also outwardly, and thus provide in thisway a support for the cart which is more stable in its operativeposition. During return swinging of each table top member 3 from itshorizontal operative position to its vertical inoperative or restposition, the reverse operation automatically takes place and the arms 8are swung back in toward the frame means to the position illustrated inEIG. 1 and in FIG. 3 for the upper right table top mem- By properchoice' of the pitch of the helical slots 12 it is possible to providefor the crank-arms 8 any desired angle of swinging in response toswinging movement of a table top member 3 between its rest and operativepositions. In the illustrated example the arms 8 are swung throughsomewhat less than as is apparent from FIG. 3.

The lower table top members 4 are respectively provided with pins 17corresponding to the pins 15 and extending through arcuate slots 18formed in the inner wall portions of the hollow end wall assemblies 1,these slots 18 also extending along circles Whose centers are the commonaxis defined by the pair of coaxial pivots 6. Thus, the upper four pins15 are respectively located over four lower pins 17.

Each pair of vertically aligned pins 15 and 17 are interconnected by anelongated push-pull bar 19 pivoted at its top end to a pin 15 and at itsbottom end to a pin 17. In this way the lower table top members 4 areconstrained to move with the upper table top members 3 in such a Waythat each pair of vertically aligned upper and lower table top membersare constrained to move in unison.

While the drawings described above show only the structure coacting withthe front ends of the table top members, as viewed in FIG. 2, and shownwithin the hollow front end wall assembly 1 of FIG. 2, it is to beunderstood that an identical structure is located in the hollow rear endwall assembly 1 of FIG. 2 coacting in the same way with the rear ends ofthe table top members 3 and 4.

The embodiment of the invention which is illustrated in FIGS. 8l0difiers from FIGS. 17 only in connection with the construction of theconnecting means between the roller arms 8 and the table top members 3,and more specifically in connection with the construction of thethreaded connection between the axially shiftable sleeves and thespindles which extend therethrough. According to this embodiment theouter surface of the spindles 7 are provided with raised threadsreceived in thread grooves formed at the inner surfaces of thesurrounding sleeves 10. For this purpose the spindles 7 respectivelyhave fixed thereto plastic inner sleeves 20 each provided at its outersurface with a pair of integral raised, relatively steep threads 21.These raised threads 21 extend into thread grooves 22 formed in theinner surfaces of the sleeves 10 which are also made of plastic. Thus,with this construction also the sleeves 10 are prevented from turningabout the axes of the spindles 7, respectively, and in response toswinging movement of the table top members 3 the pin-and-slotconnections 15, 14 will change the elevation of the sleeves to actthrough the threads 21, 22 in order to turn the spindles 7 about theiraxes and thus swing the roller arms 8. This particular embodiment hasthe advantage of providing a simpler manufacturing of the structure ofthe invention inasmuch as the threads are easily formed on die castplastic components without any particular machining or the like requiredfor this purpose. Moreover, the play in the threaded transmission isreduced, and the parts operate with a particularly small noise-level.

It is furthermore to be noted that in the structure shown in FIGS. 8 and9 the push-pull bars 19 are received in slots formed in the lateralprojections 13, the latter carrying screws or pins which extend throughthe upper openings of these push-pull bars 19. These bars are pivotallyconnected at their lower ends to the pins 17 which project from the endsof the lower table top members 4, as described above.

With the above-described structure of the invention the upper table topmembers 3 are directly coupled with the arms 8 by way of the sleeves 10and the spindles 7. It will be noted that with this construction it isonly the sleeves 10 which are required to move axially with respect tothe spindles 7. It is of course also possible to connect the lower tabletop members 4 to the arms 8 in the same way through the spindles 7, andin such a case to provide a connection by way of the push-pull bars 19from the lower table top members to the upper table top members,respectively. However, the structure described above and shown in thedrawings is preferred inasmuch as when the table top members are swungthe operator will in general directly engage the upper table top membersand thus with the illustrated construction the push-pull bars 19 neednot participate in the transmission of notion to the arms 8 which arerespectively connected with the roller assemblies 9.

In order to prevent the upwardly swung table top members which are intheir vertical inoperative positions from falling down as a result ofgravitational forces, for example, it is possible to provide at suitablelocations simple releasable locking or detent structures which can bereleased by hand for the purpose of lowering the table top members orwhich can be automatically overcome when the operator turns the tabletop members with a certain minimum force which is relatively small. Thelocking or detent structures are not illustrated in the drawings inorder not to complicate the latter excessively.

It is to be noted that a particularly simple construction is providedwith the invention at the region where the pins extend into thehorizontal slots 14 of the lateral projections 13 in order to convertthe swinging movement of the table top members 3 into axial displacementof the sleeves 10.

What is claimed is:

1. A serving cart comprising frame means, a pair of table top membersswingably carried by said frame means for turning movement with respectthereto between an operative position where said members are in a commonhorizontal plane and a rest position where said members are respectivelysituated in vertical planes, four roller assemblies for rolling on thefloor, a plurality of arms operatively connected to said rollerassemblies and extending laterally therefrom to said frame means, and apair of connecting means operatively connecting one pair of said arms toone of said table top members and the other pair of said arms to theother of said table top members, each of said connecting means beingconnected to one of said table top members and a pair of said arms forswinging said arms outwardly away from said frame means to displace theroller assemblies respectively connected to the latter pair of armsoutwardly away from said frame means in response to movement of thetable top member from its vertical rest position to its horizontaloperative position, so that when a table top member is swung to itsoperative position the rollers will swing outwardly away from said framemeans to provide the cart with greater stability.

2. The combination of claim 1 and wherein said frame means has a pair ofopposed relatively narrow end portions beyond which said table topmembers extend when they are in their horizontal operative positions,each connecting means including a pair of identical connectingassemblies respectively connected with a pair of said arms which arerespectively situated at opposed ends of said frame means and to onesaid table top members for swinging said arms outwardly away from saidframe means in response to movement of each table top member from itsvertical to its horizontal position.

3. The combination of claim 2 and wherein the pair of connectingassemblies of each connecting means includes a pair of rotary spindlesrespectively carried by said end portions of said frame means andextending in a generally vertical direction, a pair of sleevesrespectively surrounding said spindles and axially shiftable withrespect thereto while being prevented from turning, and said connectingmeans including motion transmitting elements vertically displacing saidsleeves in response to swinging of each table top member, each of saidsleeves having a threaded connection with the spindle which it surroundsfor turning the spindles and the arms connected thereto about the axesof said spindles in response to swinging each table top member.

4. The combination of claim 3 and wherein said spindles are in the formof elongated tubes, said tubes being formed at the places where theyextend through said sleeves with slots of helical configuration and saidsleeves carrying pins which extend through said slots to provide thethreaded connection between said sleeves and spindles.

5. The combination of claim 3 and wherein said spindles respectivelyhave outer surface portions surrounded by inner surface portions of saidsleeves, to provide at each sleeve an inner surface portion thereofsurrounding an outer surface portion of said spindle, one of the lattersurface portions being formed with a thread projecting therefrom and theother of said surface portions being formed with a groove having aconfiguration which matches that of and receives said thread, and theouter surface portion of said spindle being fixed thereto, so as to beincapable of rotating with respect thereto, whereby said threadedsurface portions provide the threaded connection between said sleevesand spindles.

6. The combination of claim 5 and wherein each spindle has an outersurface portion from which said threads project, said sleeves beingformed at their inner surfaces with said grooves which receive saidthreads, respectively.

7. The combination of claim 3 and wherein each sleeve has an elongatedportion projecting laterally with respect to the spindle and formed witha slot, each top member having a pin received in said slot, so thatthrough the latter pin and slot the table top is connected to the sleeveto form the connecting assembly therebetween which provides for verticaldisplacement of a sleeve in response to swinging of a table top member.

8. The combination of claim 1 and wherein said frame means include ahollow upright end wall, said connecting means including for eachswingable table top member a pair of vertically extending spindlesrespectively situated in said hollow end walls for rotary movementtherein, said spindles respectively having lower ends connected to endsof said arms which are respectively distant from a pair of said rollerassemblies, and said connecting means including a pair of sleevessituated at least approximately at the elevation of a table top mannerand through which said spindles respectively extend, said sleevesrespectively being axially shiftable on said spindles and said hollowend walls coacting with said sleeves to prevent rotary movement thereof,a pair of transmission assemblies respectively connecting each table topmember to a pair of sleeves for vertically displacing the latter inresponse to swinging movement of a table top member, and said connectingmeans including a threaded connection between said sleeves and spindlesfor turning said spindles about their axes in response to swinging ofsaid table top members.

9. The combination of claim 8 and wherein said pair of table top membersare situated one next to the other when in their vertical rest positionsand said pair of table top members having a common turning axis withrespect to said frame means.

10. The combination of claim 8 and wherein a second pair of table topmembers are respectively carried by said frame means in verticalalignment with said first-mentioned pair of table top members,respectively, and linkage 10 means linking said second pair of table topmembers with said first-mentioned pair of table top members for swingingsaid second pair of table top members respectively in unison with saidfirst-mentioned pair of table top members.

References Cited FOREIGN PATENTS 1,201,519 3/1961 Germany.

10 LEO FRIAGLIA, Primary Examiner.

ROBERT R. SONG, Assistant Examiner.

US. Cl. X.R. 1081 15

